Indirect printing methods generally include a two-step printing process including applying ink imagewise onto an intermediate transfer member, such as a drum or a belt, using an inkjet printhead, and then transferring a transient image to a substrate. After the ink is applied imagewise onto the intermediate transfer member, the ink wets or spreads on the intermediate transfer member to form a transient image. The transient image undergoes a change in properties, such as partial or complete drying, thermal or photo-curing or gelation, and is then transferred to the substrate.
Intermediate transfer members, also known as transfix belts or transfer blankets, for use in an indirect printing method are designed to satisfy a range of requirements, including wetting aqueous ink drops, heat absorption for water removal, and transfer of dried ink to the final substrate to give a clean plate.
Particularly, intermediate transfer members for use in indirect printing must meet specific sub-system requirements that are unique to the inkjet/transfix printing architecture. The intermediate transfer member desirably exhibits surface properties, such as energy, topology, and so forth, to enable wetting of the ink and subsequently, such as after the phase-change, to enable complete transfer of the transient image onto a substrate. Generally, intermediate transfer member materials that display good wettability do not sufficiently transfer the ink film onto a substrate, or conversely, do not sufficiently wet the ink but do transfer efficiently to the substrate.